Machine for tilting and lifting a load



March 15, 1960 c. BAMFORD ErAL 2,928,558

MACHINE FOR TILTING AND LIFTING A LOAD Filed April 9, 1957 A s sheets-sheet 1 March 15, 1960 c. BAMFORD ErAL 2,928,558v

MACHINE FOR TILTING AND LIFTING A LOAD 5 Sheets-Sheet 2 Filed April 9, 1957 March 15, 1960 C, BAMFORD. ETAL 2,928,558

MACHINE FOR TILTING AND LIFTING A LOAD Filed April 9, 1957 5 Sheets-Sheet 5 INVENToRs. Calw/7 Bamfofd BY Mayo 5. Pren/ce draad/CWM 17 TTORNE Y.

MACHINE FOR TILTING/AND 'LIFTING A'LOAD 5 Calvin Bamford and Mayo S. Prentice, Tacoma, Wash., assignors to Globe Machine Manufacturing Co. Inc., Tacoma, Wash., a corporation of Washington Application April 9, 1957, Serial No. 651,610

9 Claims. (Cl. 214-1) cilitating the transfer or'feeding of these articles one at a time to other machines or devices.

Another object of this invention is to provide a machine for tilting and lifting a load of large at superposed sheets of material in such a manner that the sheets can be quickly and easily handled by one .person in feeding them one at a time to other mechanism, this machine including simple and efficient devices for controlling and bringing about the tilting, lifting and lowering movements.

Another object is to provide a machine of this type which is compact and readily portable and one which can rest directly on the floor of the building in which it is used and does not require the provision ofk a pit in the loor for its installation and operation thus doing away with the inconvenience of a .floor pit and saving the expense of a floor pit and `making possible the quick and easy movementof the machinefrom one operating location to another.

Other objects of this Vinvention are to provide a machine for tilting and lifting a load which is simple and durable in construction, highly efficient in operation and not expensive to manufacture.

Other objects of this invention will ber apparent from the following description taken `in connection with the accompanying drawings.

Figure l is a detached top plan View of the base of this machine, the two upper framesbeing removed.

Fig. 2 is a front elevation of the complete machine with the two upperfframes shown -in their lowermost horizontal position.

Fig. 3 is an end elevation looking in the direction of broken line 3-3 of Fig. 2. Y

Fig. 4 is an end elevation similar to Fig. 3 but showing both of the upper frames tilted and showing the uppermost frame raised to approximately its maximum elevated position.

Fig. 5 is a combined hydraulic and electric diagram illustrating schematically the tilting and lifting devices and control means therefor.

Fig. 6 is a View in side elevation, with parts in section, taken substantially on broken line 6-6 of Fig. 4, the base frame and parts carried thereon being omitted.

Fig. 7 is a plan view, with parts in section, taken substantially on broken line 7-7 of Fig. 6 showing the tilt frame with the base frame omitted.

Like reference numerals refer to like parts throughout the several views.

The machine shown by -way of illustration in the drawings comprises a rectangular base frame B formed of end angle bars lil, side angle bars 11, cross bars 12, a longitudinally extending barv '13.and a base plate 14.4 The 2,928,558 Patented Mar. 15, 1960 ICC base plate 14 serves as a support for a pump unit `assembly comprising an electric motor 15, a tank 16 for'liquid, such as oil, used in the hydraulic devices, la pump 17, which may be disposed within the tank I6-and two electrically controlled valves 18 and 19. VThe valves I8 and 19 are connected by an oil pressure conduit 20 with the pump 17 and they control the flow of oil under pressure to hydraulic cylinders 21, 22 and 23, as hereinafter explained. A relief valve 24 can be provided in connection with the conduit 20.

A rectangular tilt frame T, formed of two end angle bars 25 and two side angle bars 26, is positioned above the base frame B in registration therewith and has 'one lateral edge portion thereof hinged to said base frame" by pivot pins 27. The pivot pins 27 pivotally connect-rigid brackets 28 on the tilt frame T with other rigid brackets 29 on the base frame B. Preferably the tilt frame T is of slightly smaller size, in plan, than the base frame B.

The two hydraulic tilt cylinders 21 and 22 are positioned between the angle bars 10 and 25 at therespective ends of the base frame B and tilt frame T. One end portion of each cylinder 21 and 22 is connected by pivot means 32 with the base frame B. A piston rod 31 protrudes from the *other end of each of said cylinders 21 and 22 and is provided with Va forked bracket '33 within which preferably three independently rotatable rollers 34, 35 and 36 are 'mounted on a bearing pin 37. Preferably the rollers 34 and 36 are 'slightly larger in diameter than the rollers 35. Each smaller roller 35 rolls'on an inclined tilt cam which is rigid with the adjacentV larger roller 34 and 36 is transversely oifset relative 'to the adjacent tilt cam 4t) and engages with the base flange of the adjacent angle bar 25 of the tilt frame. This provides low friction means for angularly moving the tilt frame T upwardly about the axis of pivots 27 in response to outward movement of the piston rods 31 in their` cylinders 21 and 22.

Two generally upright track bars 41 and 42 are frigid with the brackets 28 and are thus rigid with the corner portions of the tilt frame T. The track bars 41 and are perpendicular to the tilt frame and move angularly therewith. A cross member 43, Fig. 2, extends between the two track members 41 and 42 a short distancebelow their upper ends to add strength and rigidityv to the u'prollers 48 mounted thereon adjacent its respective ends and these rollers 48 are adapted to roll on the track bars 4l and 42 as the lift frame L moves up and down.

Two pairs of relatively crossed leveling bars connect the respective sides of the tilt frame T and lift frame L. Each pair of leveling bars'comprises two bars 49 and 5i) pivotally connected with each other mid way between their ends by a pivot member 51. The bars 49 andfSI'D v of each pair are respectively connected at one vend, by

pivot members 52 and 53, with the side angle bars 26 of the tilt frame T and the sideangle bars 46 of the lift frame L. At their `other ends the bars 49 and .5 0

of each pair are respectively provided with transversely n extending rigid bearing pins or studs 54 and 55 which project through slots56vand 56 in Vthe respective side bars 26 of the tilt frame and 46 of theY lift frame. The bearing pins 54 and 55 have rollers 57 rotatively mounted thereon. The lowermost rollers 57,-carried by. the leveling bars`50,rollwithin-trackways formed by Awelding short pieces of inverted angle bar 58 to each side bar 26. Theuppermost rollers 57, carried by the levelingV bars 49, are positioned between the bottom surface of occur if bearing pins154 and 55 were allowed to operateY in sliding contact-with the walls of the slots 56.

Upward andjdownward movement of the lift frame L is controlled by the hydraulic cylinder 23,'which has one end connected by pivot means `61 with the tilt frame Tand has'a' piston rod 6 2Aprotruding from its other end. A cross'bracket 63 on the outergend of the piston rod 62 has a bearing member 64 protrudingY from each end thereof. Two rollers 65 Vand 66 are rotatively mounted on the bearing member 64 adjacent each end of the cross bracket 63. The outermost rollers 66 areprespectively positioned in registration with two lift cams 67 which are rigidly secured to and supported by angleV bars 68. The bars 68 are rigid with tilt'frame T and extend longitudinally thereof. The twoV innermost rollers 65 are oiset inwardly from the lift cams 67 and are positioned to contact alface plate 70 on a lift arm. The lift arm has two side bars 71 and a back plate 72. The lower end of the lift arm is pivotally supported from the tilt frame by pivot means 73. The upper Yend of the lift Yarmcarries a transverse roller 74 which engages with ing `movement at the ,then attained tilt, 'and if switch 83 is held closed, will energize control81 and supply oil under pressure by way of lift control valve 19 and conduit 91 to the lift cylinder 23 and begin to move the t lift frame L upwardly parallel to track members 41 and 42. By opening and closing the foot switch 83 the lift frame L can be moved, upwardly step by step along the track members 41 and 42 and its ,upward movement accurately controlled to facilitate the successive discharge of superposed objects, such as plywood panels one after another over the roller 44. Movement of the lift frame L can be accurately controlled and it can be stopped and held at any desired elevation.- The capacity for elongation of the lift cylinderA 23 `and its piston rod 62rlimits the maximum upward movement that can be imparted to the lift frame L to substantially the position in which it is shown in Figs. 4 and 6.

To lower the lift'frame Land move it andthe tilt 'l frame T fro'mfany raised and tilted position back toward a fully lowered and horizontal position the foot switch 83 Vis opened and thefoot switch 84is momentarily closed. The closing of switch 84 energizes Vthe relay 87 and both of the electrical controls 80 and 82. The relay V87 holds the circuits to controls 80 and'SZ closed and lift arm occupies a position between thel two llft cams V67 when it is'folded and is capable of being moved into an inclined position approximately as shown in Fig. 6 :i

said controls position thevalves 18 andV 19 so that exhaust or return iiow fluid passageways are established as follows:Y From tilt cylinders 21 and 22 through conduit 90, valve 18 and conduit 92 back to tank 16 and from lift cylinder 23 through conduit 91, valve 19 and conduit 93 back to tank 16. This allows gravity to simultaneously lower theflift frame L and tiltingly `move both frames L and T back towardl a' horizontal position.

When both.` frames L and T reachtheir vlowermost hori- `zontal position, as shown inFigs. 2 and 3, they oper1 the limit switch 86 and break the-circuit torelay.87 and valve control devices 80 and 82. j p

In the usevof this device a load of large flat superposed panelsV can be placed on the deck `47 with their edges against the track members 41 and 42 when both frames L and T are in their lowermost horizontal position. To discharge these panels one ata time the operator closes the foot switch 83 whereupon the frames T and L,will first be tilted until the limit switch 85 is cuit wires 75 andA has a control circuit including a motor starter 76, a start switch 77 and a stop switch 78. The

motor 15 runs continuously during the operation of the Y machine. The valves 18 and 19 are electrically controlled and are operated bydevices such as solenoids or electromagnets indicated by 79, 80, 81 and 82. These control devices are connected by suitable" circuit means with twoA normallyopen foot switches 83 and 84,` two limit switches 85 and 86and a hold-inrelay j87 in Vthe circuit of limit`switch'86. Preferably the foot switches 83 and 84 are interconnected so that they can not both be closed at the same time,V The limitswitch 85 is a double pole or 'two way switch and is preferably mounted on the base frameB, Fig. V4, VVand connectedby flexible and adjustable means 88, which maybe a chain, with the tilt frame T. When the motor 15 is operating and the tilt frameV is horizontal or in any position below its position ofmaximum tilt the'limit switch 85 will ordinarily be in the poistion shown in Fig. 5 and closure of the foot switch 83 will energizevalve control device 79 and supply oil under pressure by way of valve 18'- and conduit,90 to b oth of the tilt cylinders 21 and2-2. Ifv

operated and then the hydraulic means will begin to move the lift frame upwardly. The operator can stop the upward movement ofthe lift frame and hold it in any desired position by opening the footswitch 83`and one operator can easily guide large panels on? over the Y transfer roller 44 and accurately position them on any panel receiving device. The feeding of large panels one at a time to lother machinesis done by sliding the top panel olf of the stackvor loadwhich rests onAthe lift frame.- Diierent materials have different textures and V- different friction characteristics, some .materials slipping moreV easilyV than others, This makes it desirable to be able to adjustthe yangle or incline at which the lift frame and panels resting thereon will bestopped. Varying the effective length "of the connector 88 between thefliniit switch'SS and -the tilt frame T provides one satisfactory way of adjusting the angle to whichthe tilt frame and lift frame and load will be moved before they. 'are stopped by the actuation ofthe limit switch 85 andthis. enables the Yoperator to control the ease vof discharge of the foot switch-s3 is Held dosed the uit frame r and lift the tilt control device 79 and close the circuit. to thel lift control device 81.- ThisV willlstop and holdfth tiltpanels. v y This machine is compact and the lift frame L can be lowered close enough Ito the oor for convenient loading without necessitating placing any parts Yof the machine ina pit. This savest he'expense of providing a tloor pit for the installation of'the'machine and saves time and expense `if the machine is to -be moved from one locationtoanother.` y y The foregoing description `and accompanying drawings clearly disclose' .a preferred embodiment of this invention but it will Vbeundcrstood thatg-this disclosure is merely illustrative and that changes may be made within the "scope'of the following claims.:

We claim:

1. In a machine for tilting andjlifting a load, a normally horizontal base frame; a tilt frame hinged to said base frame for movement between a position parallel with and a position inclined relative to said base frame; a lift frame supported parallel Vwith and carried by and movable toward and away from said tilt frame between a position in which the lift frame is closely adjacent the tilt frame and a position in which the lift frame and tilt frame are spaced a substantial distance apart; power means operable in tilting the tilt frame and lift frame relative to the base frame; and other power means operable in moving the lift frame away frompthe tilt frame.

2. In a machine for tilting and lifting a load, a normally horizontal base frame; a tilt frame having one edge portion thereof hinged to an adjoining edge portion of said base frame; a lift frame parallel with and positioned in registration with said tilt frame; bars connecting said lift frame `with said tilt frame providing parallel movement of said lift frame toward and away from said tilt frame between a position in which the lift frame is closely adjacent the tilt frame and a position in which the lift frame and tilt frame are spaced a substantial distance apart; power means operable in tilting the tilt frame and lift frame relative to the base frame; and other power means operable in moving the lift frame away from the tilt frame.

3. In a machine for tilting and lifting a load, a normally horizontal base frame; a tilt frame superposed on said base frame and having one edge portion thereof pivotally connected with an adjoining edge portion of said base frame; upright track means rigid with and substantially perpendicular to the pivoted edge portion of said tilt frame; frame tilting means interconnecting said base frame and said tilt frame providing tilting movement of said tilt frame; a lift frame positioned above and connected with said tilt frame and supported for movement toward and away from the tilt frame, said lift frame being capable of receiving a load of flat superposed articles; and frame lifting means interconnecting said lift frame and said tilt frame, said lift frame and the load thereon resting against said upright track means when said lift frame and said tilt frame are in tilted position.

4. In a machine for tilting and lifting a load of superposed dat articles, a normally horizontal base frame adapted to rest on a door; a tilt frame positioned in registration with and disposed on said base frame and having one edge portion thereof pivotally connected with an adjoining edge portion of said base frame; upright track means rigid with the pivotally mounted edge portion of said tilt frame and disposed substantially perpendicular to said tilt frame; a lift frame positioned above and connected with said tilt frame and supported for movement toward and away from said tilty frame; rollers mounted on an edge portion of said lift frame positioned to roll on said track means; a transfer roller rotatively supported by the uppermost portions of said track means and disposed parallel with the lift frame; power means operable in tilting the tilt frame and lift frame relative to the base frame; and other power means operable in moving the lift frame in a generally upward direction relative to the tilt frame.

5. In amachine for tilting and lifting a load ofsuperposed flat articles, a normally horizontal rectangular base frame; a rectangular tilt frame positioned above and capable of resting on said base frame in registration therewith and having one lateral edge portion pivotally connected with an adjoining edge portion of said base frame; two spaced apart track bars rigid with the respective corners of the pivotally mounted edge of said tilt frame and extending upwardly perpendicular to said tilt frame; a transfer roller rotatively mounted by the upper end portions of said track bars and extending between said track bars parallel with said tilt frame; a rectangular lift frame parallel with and positioned above and in registration with said tilt frame; bars connecting said lift frame and said tilt frame providing parallel movement of said lift frame toward and away Vfromsaid tilt frame; rollers mounted on an edge portion vof said lift frame positioned to roll on said upright track members; hydraulic means disposed between the base frame and the tilt frame operable in tilting the tilt frame and lift frame relative to the base frame; and other hydraulic means disposed between the tilt frame and the lift frame operable in moving the lift frame away lfrom the tilt frame. Y

6. In a machine for tilting and lifting a load, a normally horizontal base frame; a tilt frame positioned above and in registration with said base frame and having one edge portion thereof pivotally connected with an adjoining edge of said base frame; inclined cams on the base frame; roller tracks on the tilt frame adjacent said inclined cams; rollers operable between said cams and said roller tracks; hydraulic cylinders pivotally supported on the base frame and connected with said rollers for moving Vthe same in tilting said tilt frame; a lift frame positioned above and registering with and movable toward and away from said tilt frame; and hydraulic means operable in moving said lift frame away from said tilt frame.

7. In a machine for tilting and lifting a load, a normally horizontal base frame; a tilt frame positioned above and in registration with said base frame and having one edge portion thereof pivotally connected with an adjoining edge portion of said base frame; a lift frame positioned above and in registration with said tilt frame; parallel movement means connecting said tilt frame and said lift frame; hydraulic devices disposed between the base frame and the tilt frame operable in'tilting the tilt frame and lift frame relative to the base frame; other hydraulic devices disposed between the tilt frame and the lift frame operable in moving the lift frameaway 'i from the tilt frame; and electrically actuated control means controlling the operation of all of said hydraulic devices. v

8. The apparatus as claimed in claim 7 in which `a limit switch is provided in the electrically actuated control means and adjustable limit switch operating devices interconnect the limit switch Vand the tilt frame, whereby the maximum tilt of the tilt frame and lift frame can be adjusted.

9. In a machine for tilting and lifting a load, a normally horizontal base frame; a tilt frame positioned above and in registration with said base frame and having one edge portion thereof pivotally connected with an adjoining edge portion of said base frame; a lift frame positioned above and in registration with said tilt frame; parallel movement means connecting said tilt frame and said lift frame; frame tilting means interconnecting said base frame and said tilt frame providing tilting movement of said tilt frame and said lift frame; adjustable tilt limiting devices controlling said frame tilting means, whereby the amount of tilt imparted to said tilt frame and said lift frame may be varied; and Vframe lifting means interconnecting said tilt frame and said lift frame providing movement of said lift frame away from said tilt frame.

References Cited in the iile of this patent UNITED STATES PATENTS 1,547,724 Berry July 28, 1925 1,997,916 Rusnak Apr. 16, 1935 2,480,916 Gibson Sept. 6, 1949 2,686,604 Cameron Aug. 17, 1954 2,764,869 Scherr Oct. 2, 1956 2,846,085 Johnson Aug. 5, 1958 

